BOLLFILTER Automatic Backwashing Filter, Self-Cleaning Strainer welded Type 6.18

BOLLFILTER Automatic Backwashing Filter, Self-Cleaning Strainer welded Type 6.18

Flange Connection DN 500 - DN 1000 / 20" - 40"
Filter element wedge wire, longitudinal wedge wire candle or wire-mesh candle with smooth surface
Grade of filtration 10 µm - 5 mm (depending on the size of the filter)
Backflushing medium internal medium
Pressure stage PN 10 (higher pressure stages available on request)
Filter housing carbon steel
carbon steel rubber lined
stainless steel
special alloys
Features cylindrical elements open at both ends (bipolar functional principle)

Automatic backflushing filter for treatment of industrial water

The economic operation of technical systems in which large quantities of cooling water are used or accrued in open or closed circuits, service water and waste water, places the highest requirements on the filtration of the liquid. The water filters used here must

• due to precision, ensure a defined degree of purity of the liquid to be treated,
• due to reliability, ensure operation of the complete system is not interrupted and disrupted
• due to no maintenance and long service times, assist in keeping the operating costs low.

Self-cleaning backflushing filter system

The BOLLFILTER Automatic Type 6.18 optimally fulfils these requirements of an industrial water filter. With its unique bipolar operation in the filter and backflushing mode, it sets standards in water filtration. Due to its self-cleaning backflushing system and low maintenance costs, it is ideally suitable for operation in continuously operating systems – also in remote areas or without personnel on site.

Advantages of the BOLLFILTER Automatic Type 6.18

The bipolar principle of function, with cylindrical filter candles opening on two sides, has multiple advantages compared to water filters with conical or respiring candles:

• They must be replaced less often as conical and respiring candles, because the effective backflushing continuously prevents blocking of the candles. That saves costs for personnel and spare parts.
• Their separation of solids is significantly more reliable than that of respiring candles, because there is a risk that dirt particles become blocked in the lamellae of the respiring candles during the transition of backflushing to filtration and the originally defined filter fineness can no longer be attained.
• In contrast to conical and respiring candles, they can be equipped with longitudinal gap candles. Thereby, they attain a special superior cleaning result in the event of contamination by fibrous material.

Characteristics of the BOLLFILTER Automatic type 6.18 

The design of the BOLLFILTER Automatic Type 6.18 water filter is convincingly simple and robust for all precision. It is available in different sizes with nominal diameters of up to 1000 mm for volumes of flow of up to 10.000 m3/h. The sieve candles and all internal parts, attached pipelines and fittings, are made from nickel chromium molybdenum steel. The only moveable parts are the flushing arm and cover arm. Their synthetic material bushes are automatically adjusted.
The sliding bearings and flush bushes made from synthetic material are sealed to protect from contamination.


Type 6.18 / 6.19 / 6.44
Klemmplan / wiring-diagram Type 6.18-6.19 / 6.44 by BOLLFILTER ▶ Get more imformation!
Type 6.18 with E-drive
Klemmplan / wiring-diagram Type 6.18 with E-drive by BOLLFILTER ▶ Get more information!
Tightening Torques 6.18
Standard-Anziehdrehmomente für Schrauben (6.18) von BOLLFILTER ▶ Mehr erfahren!
Frank Zichel | BOLL & KIRCH

Your International Contact Person

Frank Zichel Head of Water Filtration +49 2273 562 233


Rob Eden | BOLL & KIRCH UK

Your Contact for Great Britain

Robert Eden Sales Manager Filtration Technology +44 1621 862180